Marathon Oil CEO Cazalot to retire Aug. 1

HOUSTON—Marathon Oil says CEO Clarence Cazalot Jr. is retiring, and will be replaced by an executive from ExxonMobil.

The 62-year-old Cazalot will step down as CEO on Aug. 1 but will remain as chairman through the end of the year.

He has been CEO for 11 years.

Marathon's new CEO will be 51-year-old Lee Tillman. Tillman is vice president of engineering at ExxonMobil, where he oversees engineering staff around the world. He has been at Exxon since 1989 and has held posts in Indonesia, Scotland, and Norway, as well as in the U.S.

Marathon's next chairman will be Dennis Reilley, who is currently its lead director.

Marathon Oil Corp. is an exploration and production company. It is the result of a 2011 split of the former company's refining and production businesses.